The Hydrophobic Temperature Dependence of Amino Acids Directly Calculated from Protein Structures
Fig 1
Length scale dependence of hydrophobic effect from calculations by Huang and Chandler [10] (A).
The cost of making a cavity in the water with a radius of the given size against temperature is plotted. The position of the maximum depends on the size (radius) of the solute. Small solutes with a radius of 4 Å have a peak at around 70°C, whereas larger particles with a radius of 10 Å have a peak around 40°C. An example protein structure: PDB-ID: 2K5I (B). We estimate free energies of transfer from the hydrophobic core to the surface of the protein by comparing the number of hydrophobic amino acids on the surface (small yellow spheres), to the number of buried hydrophobics (large yellow spheres), to the number of polar amino acids on the surface (small blue spheres) and to the number of buried polar amino acids (large blue spheres).